Extractable filler for inserting medicine into vertebral body

ABSTRACT

An extractable device is used to insert a medicinal filling into a vertebral body. The device comprises a filling member and a pasty medicine. The filling member is made of a flexible and permeable wall and is provided with a holding portion and an injection port via which the pasty medicine is injected into the holding portion after the filling member is inserted into the vertebral body. The holding portion is provided with an opening which is releasably lashed by one end of one or more threads so as to make the opening leakproof. Upon completion of solidification of the pasty medicine in the holding portion of the filling member, other end of the thread is pulled to unlash the opening of the holding portion, thereby enabling the filling member to be extracted from the vertebral body so as to leave only the medicine in the vertebral body.

FIELD OF THE INVENTION

The present invention relates generally to an instrument which is usedin the restorative operation of vertebral body disorder. Morespecifically this surgical instrument can be used to insert a medicalmaterial into a vertebral body such that the instrument can be separatedfrom the medical material and drawn out of the vertebral body, and themedical material solidifies in the vertebral body.

BACKGROUND OF THE INVENTION

The surgical treatment of vertebral body disorder can be generallyattained by one of three methods, which include the hypodermic injectionof medicine, the balloon-insertion of medicine, and the filler-insertionof medicine. For example, the U.S. Pat. Nos. 5,972,105; 6,066,154; and6,248,110B1 disclose respectively a method for treating bone tissuedisorders, such as osteoporosis and vertebral compression fractures. Themethod involves the use of a balloon (made by the Kyphon Crop., U.S.A.)by which the tissue is expanded to facilitate the inserting of themedicine. This balloon method is defective in design in that themedicine is apt to spread aimlessly in the tissue without boundary.Without containment, the medicine is not as effective and there is thepossibility of injury to the surrounding tissues.

In order to prevent the drawbacks of the balloon method described above,the filler-insertion method is used to implant the medicine in vertebralbody in such a way that the medicine is contained in the filler, andthat both the medicine and the filler are implanted in the vertebralbody. This filler-insertion method is often carried out in danger of thetissue rejection of the filler.

However, the aforesaid treatments do not focus on the retrieval oforiginal spinal curvature, where the front end of the vertebra havingvertebral compression fractures is relatively insufficiently supported,and the patient is apt to regain the vertebral collapse problem afterthe implantation surgery.

SUMMARY OF THE INVENTION

An extractable device for inserting a medicinal filling into a vertebralbody, said device comprising:

a filling member comprising a flexible wall and provided with a holdingportion, an injection port at one end of the holding portion, and anopening at another end of the holding portion;

one or more thread, each having one end for fastening releasably saidopening of said holding portion in such a manner that said opening isleakproof; and

a pasty medicine to be injected into said holding portion via saidinjection port of said filling member in the wake of a process forinserting said filling member into the vertebral body whereby said pastymedicine solidifies in said holding portion of said filling member;

said opening of said holding portion being unfastened at the time whenother end of said threads is pulled by an external force, therebyenabling said filling member to be extracted from the vertebral body soas to leave only said medicine in the vertebral body, wherein saidholding portion of said filling member is inflatable and issubstantially tubular after being inflated, wherein cross sectionsperpendicular to a longitudinal axis of the holding portion aresubstantially elliptical and have increasing areas thereof along adirection from the injection port to the opening of the holding portion.

Preferably, said flexible wall is provided with a plurality of throughholes and is permeable. Said flexible and permeable wall is of aone-layered or multi-layered construction.

Preferably, aid pasty medicine is a mixture of a liquid and a medicinalpowdered substance or medicinal granular substance.

Preferably, the device of the present invention further comprises aninjection tool for injecting said pasty medicine into said holdingportion via said injection port.

Preferably, said injection tool comprises a guide tube and a syringe,wherein one end of said guide tube is connected to said injection portof said filling member and another end of said guide tube is connectedto said syringe in which said pasty medicine is held, so that said pastymedicine is able to be injected into said holding portion of saidfilling member by said syringe via said injection port and said guidetube.

Preferably, the device of the present invention further comprises aworking tube for inserting into said vertebral body, so that saidfilling member together with said guide tube can be inserted into saidworking tube and said filling member can be disposed in said vertebralbody.

Preferably, said flexible wall is a folded double-layer tubular wallhaving an inner layer end and a folded double-layer end, wherein saidinjection port of said holding portion is provided at said inner layerend, and said opening of said holding portion is provided at said foldeddouble-layer end, wherein said medicine is released from said fillingmember by pulling a free end of an outer layer of the double-layertubular wall to retreat the folded double-layer end, after said openingof said holding portion being unfastened. More preferably, said one ormore thread is between an inner layer and said outer layer of saiddouble-layer tubular wall.

Preferably, said inner layer and said outer layer of said double-layertubular wall are provided with a plurality of through holes and arepermeable.

The present invention also discloses a method for implanting asolidified medicine into a vertebral body comprising:

-   -   inserting a filling member in a hole of a vertebral body, said        filling member comprising a flexible and permeable wall and        provided with a holding portion, an injection port at one end of        the holding portion, and an opening at another end of the        holding portion, wherein one or more thread is provided and each        having one end fastening releasably said opening of said holding        portion in such a manner that said opening is leakproof, wherein        said holding portion of said filling member is inflatable and is        substantially tubular after being inflated, wherein cross        sections perpendicular to a longitudinal axis of the holding        portion are substantially elliptical and have increasing areas        thereof along a direction from the injection port to the opening        of the holding portion;    -   injecting a pasty medicine into said holding portion via said        injection port of said filling member, so that said holding        portion is inflated and said pasty medicine solidifies in said        holding portion of said filling member; and    -   unfastening said opening of said holding portion by pulling        other end of said threads, thereby enabling said filling member        to be extracted from the vertebral body so as to leave only said        solidified medicine in the vertebral body,    -   wherein said solidified pasty medicine has a shape similar to        that of the inflated holding portion, and a cross section having        a greater area of said solidified medicine is closer to a        cortical rim opposite to a pedicle of said vertebral body in        comparison with a cross section having a smaller area of said        solidified medicine.

Preferably, the method of the present invention further comprisesfastening detachably an injection tool with said filling member, so thatsaid pasty medicine is injected into said holding portion via saidinjection tool. More preferably, said injection tool comprises a guidetube and a syringe, wherein one end of said guide tube is connected tosaid injection port of said filling member and another end of said guidetube is connected to said syringe in which said pasty medicine is held,wherein said pasty medicine is injected into said holding portion ofsaid filling member by said syringe via said injection port and saidguide tube.

Preferably, the method of the present invention further comprisesinserting a working tube in said hole of said vertebral body, andinserting said filling member together with said guide tube into saidworking tube, so that said filling member is disposed in said vertebralbody.

The flexible wall of the filling member of the present invention is madeof a biocompatible or biosynthetic material, such as rubber, elasticplastic, titanium, goat intestine, and the like. The flexible wall isprovided with a plurality of pores and is therefore permeable. Theflexible wall can be formed into an object in the form of sac, bag,ball, cylinder or rectangular column integrally or by joining separatepieces.

The filling member of the present invention may contain a ray imagingmaterial, such as a metal wire, by which the precise position of thefilling member can be easily located by a ray imaging system, such as anX-ray machine.

The flexible wall of the filling member of the present invention may beof a one-layered or multi-layered construction, depending on theparticle size and the viscosity of the medicine. If the particle size ofthe medicine is relatively large, the flexible wall is preferably of atwo-layered construction. If the viscosity of the medicine is relativelyhigh, the flexible wall is also preferably of a two-layeredconstruction. On the other hand, the flexible wall is preferably of athree-layered or four-layered construction under the circumstances thathe particle size of the medicine is relatively small and that heviscosity of the medicine is relatively lower.

The features and the advantages of the present invention will be morereadily understood upon a thoughtful deliberation of the followingdetailed description of the preferred embodiments of the presentinvention with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic view of an extractable filler of the presentinvention.

FIGS. 2 a and 2 b are schematic views illustrating the lashing of theopening of the holding portion of the filling member of the presentinvention.

FIG. 3 a shows a longitudinal sectional view of a one-layered wall ofthe filling member of the present invention.

FIG. 3 b shows a longitudinal sectional view of a multi-layered wall ofthe filling member of the present invention.

FIGS. 4 a and 4 b are schematic views illustrating the unlashing of theopening of the holding portion of the filling member of the presentinvention upon completion of the injection of the medicine into theholding portion of the filling member.

FIGS. 5 a and 5 b are schematic views illustrating a process in which adouble-layer wall of the holding portion of the filling member of thepresent invention is formed.

FIG. 5 c is a schematic view of the extractable filler shown in FIGS. 5a and 5 b after the double-layer wall of the holding portion of thefilling member is formed.

FIGS. 6 a to 6 c are sectional schematic views of the present inventionat work.

FIGS. 7 a and 7 b are sectional schematic views illustrating the processin which the filling member of the present invention is extracted fromthe vertebral body.

FIGS. 8 a and 8 b are schematic views illustrating that the holdingportion of the filling member of the present invention has a curvedprofile.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1, an extractable filler 10 embodied in the presentinvention comprises a filling member 20, a pasty medicine 30, a guidetube 40, and two threads 50 and 51. The filling member 20 is formed of aflexible wall 21 and is provided with a holding portion 23 and aninjection port 24. The flexible wall 21 may be made of rubber or aflexible plastic material with perforated holes. The pasty medicine 30is injected into the holding portion 23 via the guide tube 40 and theinjection port 24. The dotted line 3-3 shows a direction in which asection of the filling member 20 is taken. The holding portion 23 has ashape similar to a cone with a longitudinal axis 201, wherein two crosssections 202 and 203 perpendicular to the longitudinal axis 201 areelliptical. The cross section 202 has a short diameter 211 and a longdiameter 221, and the cross section 203 has a short diameter 212 and along diameter 222, wherein the short diameter 211 and the long diameter221 are longer than the short diameter 212 and the long diameter 222,respectively. When the filling member 20 is inserted in a collapsedvertical body, the cross section 202 is at a position closer to acortical rim opposite to a pedicle of said vertebral body and the crosssection 203 is at a position near to the cortical rim close to thepedicle of said vertebral body. Preferably, the long diameters 221 and222 are in the same direction of the vertebral column.

As shown in FIGS. 2a and 2b, the holding portion 23 of the fillingmember 20 is provided with an opening 25 opposite,to the injection port24 of the filling member 20. The opening 25 is lashed by two threads 50and 51. The first thread 50 has a first end 501 and a second end 502,while the second thread 51 has a first end 511 and a second end 512. Thetwo threads 50 and 51 are in fact fastened releasably to the flexiblewall 21 near the opening 25. The way by which they are fastened togetheris not shown in the drawing.

The opening 25 of the holding portion 22 of the filling member 20 issecurely tied up to prevent the medicine 30 from leaking out of theholding portion 22 by means of the two threads 50 and 51 which arereleasably entangled in such a manner that the first end 511 of thesecond thread 51 is wound around the first thread 50. Upon completion ofthe winding process, the flexible wall 21 surrounding the opening 25 islocated in a position between the two threads 50 and 51, as indicated bya dotted line 4-4 in FIG. 2 a. Thereafter, both ends 501 and 502 of thefirst thread 50, and the first end 511 of the second thread 51 arerespectively pulled rightward and leftwards at the same time, asillustrated in FIG. 2 b. As a result, the opening 25 of the fillingmember 20 is leakproof.

The flexible wall 21 of the filling member 20 is of a one-layeredconstruction, as shown in FIG. 3 a, or of a multi-layered construction,as shown in FIG. 3 b. The flexible wall 21 is provided with a pluralityof pores 213 permeable to fluids. If the flexible wall 21 is of amulti-layered construction, the flexible walls 21 are laminated in sucha way that the pores 213 are not corresponding in location to slow downthe passage of the fluids.

The opening 25 of the filling member 20 is untied when the second end512 of the second thread 51 is pulled upward as indicated by an arrow inFIG. 4 a. As a result, the two threads 50 and 51 become loosened.Thereafter, the first end 501 of the first thread 50 and the second end512 of the second thread 51 are respectively pulled in a direction awayfrom the opening 24 of the filling member 20, as illustrated in FIG. 5b. The opening 25 is thus unfastened completely.

A further embodiment of the present invention is shown in FIGS. 5 a, 5 band 5 c, which is similar to the embodiment shown in FIGS. 1 to 4 b,except that a filling member 60 is formed of a double-layer wall 61 andthe first thread 51 and second thread 52 are located between an innerlayer 612 and an outer layer 611 of the double-layer wall 61. As shownin FIGS. 5 a and 5 b, a flexible and permeable tubular wall having aninjection port 64 at one end is tied at an intermediate point thereof bythe threads 50 and 51 at the beginning. The lower portion 611 of thetubular wall (will become an outer layer) is then rolled up, so that itis inside out and covering up the threads 50 and 51 and the upperportion 612 of the tubular wall (will become an inner layer). Therolled-up end of said double-layer wall 61 is provided with an opening52 of the holding portion 63, which is lashed by the two threads 50 and51. The holding portion 63 as shown in FIG. 5 c has a conic shapesimilar to the embodiment shown in FIG. 1. The opening 65 can beunfastened by pulling the threads 50 and 51 the same way as shown inFIGS. 4 a and 4 b.

As shown in FIGS. 6 a to 6 c, the filling member 60 of the extractablefiller 10 is inserted into a hole 81 formed on a vertebral body 80,wherein a working tube 43 is inserted into the hole 81 in advance toaccommodate the guide tube 40, the threads 50 and 51 and the free end ofthe outer layer 611 of the double-layer wall 61 of the filling member60. The pasty medicine 30 is then injected into the holding portion 63of the filling member 60 by a syringe 70 in conjunction with the guidetube 40. The guide tube 40 has one end 41 in the holding portion 63, andanother end 42 connected to one end 711 of a barrel 71 of the syringe70. A plunger 72 is slidably inserted into another end 712 of the barrel61 in which the pasty medicine 30 is contained. The filling member 60 isthus inflated by the medicine 30, as shown in FIGS. 6 b and 6 c, whereinthe greater cross section thereof is at a position closer to a corticalrim opposite to a pedicle of said vertebral body and the smaller crosssection thereof is at a position near to the cortical rim close to thepedicle of said vertebral body. Preferably, the long diameters of theelliptical cross sections of the pasty medicine 30 are in the samedirection of the vertebral column indicated by a dot line 82 in FIG. 6c, thereby there may be enough room in the vertical body 80 forimplanting two pasty medicines 30.

The pasty medicine 30 is a mixture of a liquid and one or more kinds ofvertebral body drugs in the form of powder, granule, or colloid. Thepasty medicine 30 is capable of solidification.

Upon completion of the solidification of the pasty medicine 30 in thevertebral body 80, the filling member 60 must be extracted from the hole81 of the vertebral body 80, so as to leave only the medicine 30 in thevertebral body 80 to prevent the rejection of the filling member 60 bythe human body. The extraction of the filling member 60 from the hole 81of the vertebral body 80 involves a first step in which the second end512 of the second thread 51 is pulled upward as indicated by an arrow inFIG. 4 a. As a result, the two threads 50 and 51 become loosened.Thereafter, the first end 501 of the first thread 50 and the second end512 of the second thread 51 are respectively pulled in a direction awayfrom the opening 24 of the filling member 20, as illustrated in FIG. 4b. The opening 65 is thus unfastened completely.

After the opening 65 being unfastened, the rolled-up double-layer end isretreated from the solidified medicine 30 by pulling a free end of theouter layer 611 of the double-layer wall 61, while one end of the innerlayer 612 is connected to the guide tube 40 as an injection port of saidholding portion of the said filling member 60, whereby said solidifiedmedicine 30 is released from said filling member 60 and is disposed inthe vertebral body 80, as shown in FIGS. 7 a and 7 b. The filling memberand the guide up 40 are pulled from the hole 81 of the vertebral body80, so as to leave only said solidified medicine 30 in the vertebralbody 80.

As shown in FIGS. 8 a and 8 b, the flexible wall 91 of the fillingmember 90 of the extractable filler 10 of the present invention may havea curved profile. Accordingly, the pasty medicine injected into thefilling member 90 in the vertebral body will also has a curved profile.

The embodiments of the present invention described above are to beregarded in all respects as being illustrative and nonrestrictive.Accordingly, the present invention may be embodied in other specificforms without deviating from the spirit thereof. The present inventionis therefore to be limited only the scopes of the following claims.

1. An extractable device for inserting a medicinal filling into a vertebral body, said device comprising: a filling member comprising a flexible wall and provided with a holding portion, an injection port at one end of the holding portion, and an opening at another end of the holding portion; one or more thread, each having one end for fastening releasably said opening of said holding portion in such a manner that said opening is leakproof; and a pasty medicine to be injected into said holding portion via said injection port of said filling member in the wake of a process for inserting said filling member into the vertebral body whereby said pasty medicine solidifies in said holding portion of said filling member; said opening of said holding portion being unfastened at the time when other end of said threads is pulled by an external force, thereby enabling said filling member to be extracted from the vertebral body so as to leave only said medicine in the vertebral body, wherein said holding portion of said filling member is inflatable and is substantially tubular after being inflated, wherein cross sections perpendicular to a longitudinal axis of the holding portion are substantially elliptical and have increasing areas thereof along a direction from the injection port to the opening of the holding portion.
 2. The device as defined in claim 1, wherein said flexible wall is provided with a plurality of through holes and is permeable.
 3. The device as defined in claim 2, wherein said flexible and permeable wall is of a one-layered or multi-layered construction.
 4. The device as defined in claim 1, wherein said pasty medicine is a mixture of a liquid and a medicinal powdered substance or medicinal granular substance.
 5. The device as defined in claim 1 further comprising an injection tool for injecting said pasty medicine into said holding portion via said injection port.
 6. The device as defined in claim 5, wherein said injection tool comprises a guide tube and a syringe, wherein one end of said guide tube is connected to said injection port of said filling member and another end of said guide tube is connected to said syringe in which said pasty medicine is held, so that said pasty medicine is able to be injected into said holding portion of said filling member by said syringe via said injection port and said guide tube.
 7. The device as defined in claim 6 further comprising a working tube for inserting into said vertebral body, so that said filling member together with said guide tube can be inserted into said working tube and said filling member can be disposed in said vertebral body.
 8. The device as defined in claim 1, wherein said flexible wall is a folded double-layer tubular wall having an inner layer end and a folded double-layer end, wherein said injection port of said holding portion is 1 provided at said inner layer end, and said opening of said holding portion is provided at said folded double-layer end, wherein said medicine is released from said filling member by pulling a free end of an outer layer of the double-layer tubular wall to retreat the folded double-layer end, after said opening of said holding portion being unfastened.
 9. The device as defined in claim 8, wherein said one or more thread is between an inner layer and said outer layer of said double-layer tubular wall.
 10. The device as defined in claim 9, wherein said inner layer and said outer layer of said double-layer tubular wall are provided with a plurality of through holes and are permeable.
 11. A method for implanting a solidified medicine into a vertebral body comprising: inserting a filling member in a hole of a vertebral body, said filling member comprising a flexible and permeable wall and provided with a holding portion, an injection port at one end of the holding portion, and an opening at another end of the holding portion, wherein one or more thread is provided and each having one end fastening releasably said opening of said holding portion in such a manner that said opening is leakproof, wherein said holding portion of said filling member is inflatable and is substantially tubular after being inflated, wherein cross sections perpendicular to a longitudinal axis of the holding portion are substantially elliptical and have increasing areas thereof along a direction from the injection port to the opening of the holding portion; injecting a pasty medicine into said holding portion via said injection port of said filling member, so that said holding portion is inflated and said pasty medicine solidifies in said holding portion of said filling member; and unfastening said opening of said holding portion by pulling other end of said threads, thereby enabling said filling member to be extracted from the vertebral body so as to leave only said solidified medicine in the vertebral body, wherein said solidified pasty medicine has a shape similar to that of the inflated holding portion, and a cross section having a greater area of said solidified medicine is closer to a cortical rim opposite to a pedicle of said vertebral body in comparison with a cross section having a smaller area of said solidified medicine.
 12. The method as defined in claim 11, wherein said pasty medicine is a mixture of a liquid and a medicinal powdered substance or medicinal granular substance.
 13. The method as defined in claim 11 further comprising fastening detachably an injection tool with said filling member, so that said pasty medicine is injected into said holding portion via said injection tool.
 14. The method as defined in claim 13, wherein said injection tool comprises a guide tube and a syringe, wherein one end of said guide tube is connected to said injection port of said filling member and another end of said guide tube is connected to said syringe in which said pasty medicine is held, wherein said pasty medicine is injected into said holding portion of said filling member by said syringe via said injection port and said guide tube.
 15. The method as defined in claim 14 further comprising inserting a working tube in said hole of said vertebral body, and inserting said filling member together with said guide tube into said working tube, so that said filling member is disposed in said vertebral body. 